According to the latest research, the Epstein-Barr virus (EBV) may be the leading cause of multiple sclerosis (MS). MS is an autoimmune condition in which the body attacks the myelin (protective coating) of nerve cells in the central nervous system (brain and spinal cord). Scientists now believe that EBV is not only involved in how MS develops — but also how it progresses and how severe it becomes.

Researchers still don’t fully understand EBV’s effect on the course of MS (including severity and progression). However, they’ve found interesting links between MS progression and severity and antibodies that indicate EBV infection.

What Is the Epstein-Barr Virus?

EBV is an extremely common human herpes virus. EBV is known as a cause of infectious mononucleosis (“mono”). More than 90 percent of the adult population worldwide has been exposed to EBV at some point in their lives, but EBV does not appear to cause serious illness. In some people, however, infection with the virus has been linked to MS, as well as other autoimmune diseases and some types of cancer such as lymphoma.

EBV can infect epithelial cells (such as those that line the mouth and throat). However, it’s mostly found in B lymphocytes or B cells, which are a type of white blood cell in the immune system. These infected cells live longer than normal, allowing for the virus to remain in the body in a latent (dormant) state.

How Does EBV Influence MS?

Over the past 40 years, scientists have explored the connection between EBV infection and MS. Although researchers believe EBV contributes to the development of MS, other risk factors are also important. A combination of genetic risk factors and other environmental risk factors likely lead to the development of MS.

Once a person develops MS, EBV is still present in their body. According to research, both the severity and disease progression of MS can correlate with how the immune system reacts to the virus. EBV produces viral proteins that cause an immune response in the body. This immune response causes the body to make antibodies against the proteins. Blood tests for EBV include tests for these antibodies, and having these antibodies in your blood means you are “seropositive” for EBV.

The body produces antibodies to various EBV proteins at different times during EBV infection. Antibodies against EBV appear first during acute infection. Some will persist at lower levels throughout a person’s life, while others will be indetectable in most people after six months. After the acute infection has passed, the body creates other antibodies that are detectable for the rest of a person’s life.

Researchers have found that levels of these antibodies against EBV can change during the course of MS. Blood test results for these antibodies correlate with MS disease activity, such as relapses and progression of MS. Levels of these antibodies can also differ among various types of MS.

EBV is not only involved in the development of MS; it also plays a role in determining the course of the disease. Scientists believe that the reactivation of EBV in the body plays a role in how MS relapses and progresses.

Understanding the Potential Role of EBV in MS

For now, experts only know part of the story of how EBV and MS are linked, but scientific research may uncover much more in the future. A better understanding of how EBV influences MS may lead to improved treatments or strategies to help prevent MS.

Understanding how EBV antibody levels influence MS disease progression may help doctors assess MS. Talk to your doctor about what blood tests could help monitor the course of your MS. These tests may complement magnetic resonance imaging (MRI) to track MS lesions in the central nervous system.

Living with a chronic disease like MS can be scary and frustrating, but learning more about your disease and understanding what is going on inside your body can help you cope.

Talk With Others Who Understand

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